Gathering text via Serial Port

I'm attemting to gather text via the serial port. Using the snippet included with VB 2005, I'm not certain how to extract the info gathered and stored in the StringBuilder.

What I'm doing is simply sending text from one machine to another <--- running my application, and displaying it in a text box. When I attempt to do this in the DataReceived method, I get thread exception errors. Seems I can't access textbox controls while in the DataReceived method, but I am able to display the info via MessageBox.show().

Tony
Beginner Programmer

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Gathering text via Serial Port

RWBitters

I cant get it how do I use faill safe asigment to the text box

I cant get the sample codes to run
DONG
Found my problem. Read a post by Harry discussing "Making thread-safe calls to Windows Forms Controls."

Code you might need to do this:
***Note*** I open my port in frmMain_Load and close my port in frmMain_FormClosed

Delegate Sub SetTextCallback(ByVal [text] As String)

Private Sub SerialPort1_DataReceived (ByVal sender As Object,
         ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles rs232.DataReceived

         If e.EventType <> SerialData.Chars Then Exit Sub

         Dim inData As String = rs232.ReadLine

         DisplayText(inData)

End Sub

'This method demonstrates a pattern for making thread-safe

'TextBox Displays

Private Sub DisplayText(ByVal [text] As String)

   'InvokeRequired required compares the thread ID of the

   'calling thread to the thread ID of the creating thread.

   'If these threads are different, it returns true

   If Me.RichTextBox1.InvokeRequired Then

      Dim d As New SetTextCallback(AddressOf DisplayText)

      Me.Invoke(d, New Object() {[text]})

   Else

      Me.RichTextBox1.Text += [text]

   End If

End Sub

Sub SendSerialData(ByVal data As String)

   rs232.Write(data & Chr(13))

End Sub
Gathering text via Serial Port

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